Just breath, it will be o.k. Don't panic about trying to give your friends a great experience, they will be a WDW, even if they don't ride a single ride and it rains every day, they will be a WDW so just plan to enjoy that. Don't try to overplan or make everything wonderful for everyone, it's impossible and it would be setting everyone up for disappointment. They are going to enjoy it and hopefully be very thankful for all the planning you did. We have taken a number of people for their first adult trips, they always ask us why we want to go to a kid's place when we are not kids. After about 30 minutes they understand and I don't plan a thing. Not even FPs until about a week out, more often than not the day before. We make it a point to point out the beauty, look up, stop and smell the roses (literally). We've had two people we've taken end up buying DVC when they told us before they went they knew they were going to hate it.